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Perhaps one of the most interesting features noted in the analysis this year has to do with the <br />process of forest development along streams such as Coal Creek. <br />First, it is clear just how damaging poorly managed grazing is to riparian vegetation. In 2007, <br />it took only a month for vegetation, primarily herbaceous growth, outside the exclosures to <br />essentially equal the growth within the exclosures. Woody vegetation also showed improvement <br />outside the exclosures, but woody plants will be slower to respond to the removal of grazing impact. <br />Nevertheless, they too showed some improvement in the second half of the 2007 growing season. <br />Among the older cottonwoods that had been browsed heavily, protection allowed a rapid recovery of <br />leaf surface area and rapid recovery from extreme damage in previous years. This is especially <br />evident in Exclosure 3 where the trees that looked like they were tornado damaged before protection <br />recovered to produce essentially a wall of cottonwood branches and leaves after two seasons of <br />protection. <br />Actually, this is not new information. It has been known for a many years that cattle grazing <br />in riparian areas in arid and semi-and lands is extremely destructive if done in a poorly managed <br />fashion. That said, many studies have also shown that cattle grazing in riparian areas is entirely <br />possible if done in a way that is sensitive to the growth patterns in riparian comdors. <br />Second, and certainly less obvious, is the evidence for the pattern of development of woody <br />vegetation in its eazly stages in riparian corridors. For this, one must look closely at Exclosure 1 and <br />to a lesser extent Exclosure 2. In 2007, an almost complete reversal of the numerical dominance of <br />willow and cottonwood occurred in Exclosure 1. This is also faintly evident in Exclosure 2, but there <br />the woody growth is still gaining in density and therefore not showing the kinds of complex <br />developmental patterns evident in Exclosure 1. <br />Around the shore of new lakes, invasion of woody plants tends be intensely zonal. Near the <br />waterline, herbaceous wetland plants invade and these extend a short distance up the shore, but <br />dominate the growth very near the waterline. Depending on the grade of the lakeshore, the next zone <br />is dominated by willow with an understory of some wetland plants. Slightly higher is the cottonwood <br />zone which can extend to where the distance from the surface to the water table is about four or five <br />feet. Beyond that woody growth, if it develops, is mostly dominated by somewhat dryland trees and <br />shrubs with very deep roots. <br />In Exclosure 1, this kind of zonation is not evident or if evident is more of an illusion than a <br />reality. Along streams the development patterns can apparently be more complex. There is still the <br />limitation of the distance from the surface to groundwater that patterns the very generalized zonation <br />around lakes, but in the ephemeral stream channel the specific invasion patterns show so much <br />overlap of the lakeshore zones that zones are almost invisible, if they exist at all. <br />In 2006, the wetter aeeas were numerically dominated by willows and the drier areas <br />numerically dominated by cottonwood. Thus, in 2006, the vegetation patterns appeazed to be <br />showing a typical lakeshore type of development. But in 2007, willow declined in the wet areas <br />2007 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 25 <br />